Temporal patterns of cytokine and injury biomarkers in hospitalized COVID-19 patients treated with methylprednisolone

Background

The novel coronavirus disease 2019 (COVID-19) presents with complex pathophysiological effects in various organ systems. Following the COVID-19, there are shifts in biomarker and cytokine equilibrium associated with altered physiological processes arising from viral damage or aggressive immunological response. We hypothesized that high daily dose methylprednisolone improved the injury biomarkers and serum cytokine profiles in COVID-19 patients.

Methods

Injury biomarker and cytokine analysis was performed on 50 SARS-Cov-2 negative controls and 101 hospitalized severe COVID-19 patients: 49 methylprednisolone-treated (MP group) and 52 placebo-treated serum samples. Samples from the treated groups collected on days D1 (pre-treatment) all the groups, D7 (2 days after ending therapy) and D14 were analyzed. Luminex assay quantified the biomarkers HMGB1, FABP3, myoglobin, troponin I and NTproBNP. Immune mediators (CXCL8, CCL2, CXCL9, CXCL10, TNF, IFN-γ, IL-17A, IL-12p70, IL-10, IL-6, IL-4, IL-2, and IL-1β) were quantified using cytometric bead array.

Results

At pretreatment, the two treatment groups were comparable demographically. At pre-treatment (D1), injury biomarkers (HMGB1, TnI, myoglobin and FABP3) were distinctly elevated. At D7, HMGB1 was significantly higher in the MP group (p=0.0448) compared to the placebo group, while HMGB1 in the placebo group diminished significantly by D14 (p=0.0115). Compared to healthy control samples, several immune mediators (IL-17A, IL-6, IL-10, MIG, MCP-1, and IP-10) were considerably elevated at baseline (all p≤0.05). At D7, MIG and IP-10 of the MP-group were significantly lower than in the placebo-group (p=0.0431, p=0.0069, respectively). Longitudinally, IL-2 (MP-group) and IL-17A (placebo-group) had increased significantly by D14. In placebo group, IL-2 and IL-17A continuously increased, as IL-12p70, IL-10 and IP-10 steadily decreased during follow-up. The MP treated group had IL-2, IFN-γ, IL-17A and IL-12p70 progressively increase while IL-1β and IL-10 gradually decreased towards D14. Moderate to strong positive correlations between chemokines and cytokines were observed on D7 and D14.

Conclusion

These findings suggest MP treatment could ameliorate levels of myoglobin and FABP3, but appeared to have no impact on HMGB1, TnI and NTproBNP. In addition, methylprednisolone relieves the COVID-19 induced inflammatory response by diminishing MIG and IP-10 levels. Overall, corticosteroid (methylprednisolone) use in COVID-19 management influences the immunological molecule and injury biomarker profile in COVID-19 patients.

Effects of feeding 25-hydroxyvitamin D3 with an acidogenic diet during the prepartum period in dairy cows: Mineral metabolism, energy balance, and lactation performance of Holstein dairy cows

Our objective was to determine the effects of feeding 25-hydroxyvitamin D₃ [25(OH)D₃], or vitamin D₃ (cholecalciferol) on plasma, mineral, and metabolite concentrations, mineral balance, mineral excretion, rumination, energy balance, and milk production of dairy cows. We hypothesized that supplementing 3 mg/d of 25(OH)D₃ during the prepartum period would be more effective than supplementing vitamin D₃ at the National Research Council (2001) levels to minimize calcium imbalance during the transition period and improve milk production of dairy cows. Forty multiparous, pregnant nonlactating-Holstein cows were enrolled in this study. Body weight, body condition score, parity, and milk yield in the previous lactation (mean ± standard deviation) were 661 ± 59.2, 3.46 ± 0.35, 1.79 ± 0.87, and 33.2 ± 6.43 kg/d, respectively. Cows were enrolled into the blocks (n = 20 for each treatment) at 30 d of the expected day of calving to receive an acidogenic diet (373 g/kg of neutral detergent fiber and 136 g/kg of crude protein, dry matter basis; -110 mEq/kg) associated with the treatments: (1) control (CTRL), vitamin D₃ at 0.625 mg/d (equivalent to 25,000 IU of vitamin D₃/d) or (2) 25(OH)D₃ at 3 mg/d (equivalent to 120,000 IU of vitamin D₃/d). All cows were fed with the base ration for 49 d after calving. Blood samples were taken on d 7, 0, 1, 2, 21, and 42, relative to calving. No effect of treatment was observed for prepartum dry matter intake or body condition score. A trend for increase of ionized Ca was observed for the cows fed 25(OH)D₃, compared with the CTRL, but no effect of treatment was detected for total Ca or total P. Feeding 25(OH)D₃ increased colostrum yield. The plasmatic concentration of 25-hydroxyvitamin D₃ was increased with 25(OH)D₃ supplementation. 25-Hydroxyvitamin D₃ supplementation increased plasma glucose concentration at parturition. The postpartum dry matter intake was not influenced by treatments. Feeding 25(OH)D₃ increases milk yield, 3.5% fat-corrected milk, and energy-corrected milk and improves milk yield components in early lactation. Overall, these findings suggest that 25(OH)D₃ at 3 mg/d can improve the energy metabolism and lactation performance, compared with the current-feeding practice of supplementing vitamin D₃ at 0.625 mg/d.

Diversity of Calliphoridae and Mesembrinellidae (Diptera: Oestroidea) in a Mangrove, Restinga, and Forest Landscapes From a Lagoon Complex on an Atlantic Forest Coastline (Rio de Janeiro, Brazil)

Diptera Mesembrinellidae present great ecological importance as potential bioindicators and Calliphoridae stand out for their medical-sanitary importance as potential vectors of pathogens and causes of human and animal diseases such as myiasis. They beneficially aid in elucidating crimes in forensic entomology, contributing to determine the postmortem interval (PMI) and assisting in the healing process of necrotic wounds in larval therapy. This study aimed to inventory the Calliphoridae and Mesembrinellidae fauna in order to evaluate structural parameters and to apply faunal indexes in catching species in the Itaipu-Piratininga lagoon complex, in Niterói (Rio de Janeiro), Brazil. The collections were carried out monthly from September 2015 to August 2016 with fish bait (sardines) exposed for 48 h, totaling six traps installed in three physiognomies (mangrove, ombrophilous forest, and restinga). In total, 9,773 individuals were captured, divided into two families, five genera, and 11 species. Chrysomya megacephala (Fabricius, 1794) was the predominant species, while Mesembrinella bellardiana (Aldrich, 1922) was the least representative species, indicating the preservation level of this ecosystem. Ombrophilous forest was the physiognomy with greater diversity and restinga was the physiognomy with greater species dominance. The similarity index indicated greater similarity among the mangrove and restinga populations.

Electrodialytic removal of tungsten and arsenic from secondary mine resources - Deep eutectic solvents enhancement

Tungsten is a critical raw material for European and U.S. economies. Tungsten mine residues, usually considered an environmental burden due to e.g. arsenic content, are also secondary tungsten resources. The electrodialytic (ED) process and deep eutectic solvents (DES) have been successfully and independently applied for the extraction of metals from different complex environmental matrices. In this study a proof of concept demonstrates that coupling DES in a two-compartment ED set-up enhances the removal and separation of arsenic and tungsten from Panasqueira mine secondary resources. Choline chloride with malonic acid (1:2), and choline chloride with oxalic acid (1:1) were the DES that in batch extracted the average maximum contents of arsenic (16%) and tungsten (9%) from the residues. However, when ED was operated at a current intensity of 100 mA for 4 days, the extraction yields increased 22% for arsenic and 11% for tungsten, comparing to the tests with no current. From the total arsenic and tungsten extracted, 82% and 77% respectively were successfully removed from the matrix compartment, as they electromigrated to the anolyte compartment, from where these elements can be further separated. This achievement potentiates circular economy, as the final treated residue could be incorporated in construction materials production, mitigating current environmental problems in both mining and construction sectors.

Immunization with the recombinant myosin regulatory light chain (FhrMRLC) in Adjuplex® adjuvant elicits a Th1-biased immune response and a reduction of parasite burden in Fasciola hepatica infected rats

The aim of this study was to assess the immune response and the protective efficacy elicited by the vaccination with the recombinant Fasciola hepatica myosin regulatory light chain (FhrMRLC) in Adjuplex® adjuvant against the infection with F. hepatica in rats. Four groups of 15 animals each were used for the study, one group was immunized with the recombinant F. hepatica MRLC in Adjuplex® adjuvant and the other groups remained as adjuvant, positive and negative control groups. The parasitological study showed that a statistically significant reduction of 65.1% and 82.1% in fluke burden and fecal egg count, respectively, was detected in vaccinated animals. In addition, vaccination with FhrMRLC induced a well-defined humoral and cellular immune response characterized by a significant production of specific IgG and IL-2, IL-12, TNF-α and IFN-γ; which confirms the immunogenic capacity of the FhrMRLC.

P2516Cardiac rehabilitation program - experience and outcomes in a tertiary center

Introduction

Cardiac rehabilitation (CR) programs are effective in improving functional capacity and reducing mortality. The level of adherence to them seems to be less than the ideal, and some factors can predict non-compliance with impact on outcomes.

Purpose

The aim was to characterize the population of the cardiac rehabilitation (CR) appointment, determine factors predictive of compliance with the standard CR exercise program and evaluate the benefits of the program.

Methods

Retrospective analysis of patients in a CR appointment at a single center between 2014 and 2017. Patients (P) were divided into two groups: compliance >80% of the program (GI) and non-compliance (GII). We assessed clinical, laboratory, and echocardiographic characteristics and determined predictors for compliance and compared the follow-up to date.

Results

270P (83% men) were included, with a mean age of 57 years. The P had a median follow up of 35 months, with an interquartil interval of 28 months. The majority (92.5%) had at least one cardiovascular risk factor (25.1% diabetes, 57.1% hypertension, 72.8% dyslipidemia, 75.8% obesity or weight excess, with mean body mass index (BMI) 27.3±3.46, 16.7% family history, 19.8% acute myocardial infarction (AMI), 48.2% smoking). 99% of the patients were medicated (93.7% acetylsalicylic acid, 67.3% clopidogrel, 24.1% ticagrelor, 95.6% beta-blocker, 93.7% ACEI/ARB, 95.5% statin). 144P (53.3%) were not from Lisbon. Most patients (77%) were referred after AMI, 8.9% with heart failure (HF), 8.5% with stable or unstable coronary disease and 1.9% with valvulopathy. 69P (25.6%) attended >80% of the CR program. Death occurred in 4.4% of the P (71.4% cardiovascular causes) and 27% had at least 1 hospitalization. Age, sex, economic insufficiency and residence local (Lisbon or non-Lisbo) were not predictors of non-compliance (p=0.859, p=0.656, p=0.914 and p=0.515 respectively). Predictors of non-compliance were higher IMC (CC=-0.141, p=0.014), higher cholesterol (CC=-0.140, p=0.016), higher C reactive protein (CC=-0.120, p=0.043), higher HbA1c (CC=-0.170, p=0.008) and CR for heart failure (HF) (OR = 0.715, IC [0.659–0.775], p=0.002). Of these, higher HbA1C (p=0.018) and CR for HF (p=0.034) were independent predictors. Compliance with>80% of the program was associated with lower overall mortality (OR = 0.732, IC [0.679–0.788], p=0.037), but not as an independent factor (p=0.378). The only independent predictor of mortality were BNP (p<0.0001).

Conclusion

Of the patients referred to the CR consultation one fourth concludes the program. Several factors can predict non-compliance, with higher HbA1c and CR for HF being independent predictors. Compliance with the CR program is associated with lower overall mortality.

P2510Cardiorespiratory optimal point as a predictor of outcomes in patients enrolled in a cardiac rehabilitation program

Introduction

The cardiopulmonary exercise test (CEPT) allows the evaluation of peak and sub-maximal tolerance to the effort, giving us relevant information for clinical decisions. Evidence has emerged that Cardiorespiratory Optimal Point (COP)>30, calculated as the minimum ratio between ventilation and oxygen (VE/VO2) may be a good predictor of events.

Purpose

The aim was to characterize the population of the cardiac rehabilitation (CR) appointment that performed CEPT, evaluate COP as a predictor of events and determine the best cut off for our population.

Methods

Retrospective analysis of CR appointment patients who performed CEPT between 2014 and 2017 in a single center. We compared the mortality and hospitalizations according to COP and COP>30. We established the appropriate Cut Off for our population and compared the same with the occurrence of events.

Results

207Patients (P) (83.6% men) were included, with a mean age of 57 years. The mean COP was 23.6±5.8 (IC [24.06–25.66]). 15.9% P had COP >30 and 33.8% had COP<22. The majority (96.6%) had a cardiovascular disease or risk factors and 99% were medicated. The majority (87.9%) was referred for CR with isquemic cardiopathy (AMI or stable or unstable coronary disease), 9.2% with heart failure (HF) and 9.2% with valvulopathy. 6.9% P died from any cause, 33.8% had an hospitalization (78.6% from a cardiovascular reason). Higher COP values correlated with higher number of all causes hospitalizations (H) (CC = 0.123, p=0.032), cardiovascular H (CC = 0.123, p=0.032), heart failure H (CC = 0.189, p=0.001) and device placement H (CC = 0.173, p=0.003). COP did not correlate with mortality (p=0.453). The cut off of 30 only correlated with HF hospitalization in this population (OR = 5, IC [1.429–17.494] p=0.006). In our population, COP was a good predictor for all cause H and heart failure H (AUC = 0.8 in both). A cut off of 25 had a sensitivity (S) of 78% with a specificity (E) of 70% for all cause hospitalization and S 73% and E 68% for heart failure H. Values above this cut off correlate with more all cause H (OR = 1,928, IC [1.06–3.507], p=0.031) and heart failure H (OR = 5.63, IC [1,44–21.94]), p=0.006). COP was an independent predictor of all-cause H (p=0.018) and heart failure H (p<0.0001). Other independent predictors of HF hospitalization are BNP (p=0.0011) and ejection fraction (p<0.0001).

Conclusion

COP was a good independent predictor of all-cause hospitalizations and HF hospitalization. In our population the cut off 25 for COP had the greatest S and E for predicting events. In our population this factor was not a good predictor of mortality.

An update on the aspects of Zika virus infection on male reproductive system

Zika virus (ZIKV) is mainly transmitted through Aedes mosquito bites, but sexual and post-transfusion transmissions have been reported. During acute infection, ZIKV is detectable in most organs and body fluids including human semen. Although it is not currently epidemic, there is a concern that the virus can still reemerge since the male genital tract might harbor persistent reservoirs that could facilitate viral transmission over extended periods, raising concerns among public health and assisted reproductive technologies (ART) experts and professionals. So far, the consensus is that ZIKV infection in the testes or epididymis might affect sperm development and, consequently, male fertility. Still, diagnostic tests have not yet been adapted to resource-restricted countries. This manuscript provides an updated overview of the cellular and molecular mechanisms of ZIKV infection and reviews data on ZIKV persistence in semen and associated risks to the male reproductive system described in human and animal models studies. We provide an updated summary of the impact of the recent ZIKV outbreak on human-ART, weighing on current recommendations and diagnostic approaches, both available and prospective, with special emphasis on mass spectrometry-based biomarker discovery. In the light of the identified gaps in our accumulated knowledge on the subject, we highlight the importance for couples seeking ART to follow the constantly revised guidelines and the need of specific ZIKV diagnosis tools for semen screening to contain ZIKV virus spread and make ART safer.

Ferrule Design Does Not Affect the Biomechanical Behavior of Anterior Teeth Under Mechanical Fatigue: An In Vitro Evaluation

Objectives:

To investigate the survival and failure mode of fiber-post resin restorations over preparations with different ferrule designs when submitted to a fatigue load test.

Methods and Materials:

Fifty bovine incisors were selected and divided into five groups (n=10) according to ferrule design: a no-ferrule group, a 2-mm circumferential ferrule group, a 2-mm buccal ferrule group, a 2-mm lingual ferrule group, and a 2-mm buccal and lingual ferrule group. The fiberglass post was cemented and the composite core was built up and prepared, followed by cementation of a full composite crown. The samples were subjected to a cyclic fatigue test with loading applicator at 135°; a staircase approach was used until fracture. Survival (cycles to fracture) and failure modes were recorded. Survival data were analyzed with the log-rank test, while Kruskal-Wallis and Fisher exact tests were used to analyze failure mode data (α=0.05).

Results:

The median number of cycles to fracture ranged from 215,000 to 236,153. The log-rank test showed no statistically significant difference in survival rates among the groups (p=0.82). Regarding failure mode, three types were observed: I, post and/or core fracture; II, root fracture in the cervical third; and III, root fracture in the middle third. No statistical difference was observed among the groups (Kruskal-Wallis test, p=0.147).

Conclusion:

The ferrule design had no effect on fatigue resistance or failure mode of endodontically treated incisor teeth restored with a fiber post, composite core buildup, and composite crown.

Composition of sand fly fauna (Diptera: Psychodidae) and detection of Leishmania DNA (Kinetoplastida: Trypanosomatidae) in different ecotopes from a rural settlement in the central Amazon, Brazil

Background

Phlebotomine sand flies (Diptera: Psychodidae) are vectors of Leishmania species, the etiological agents of leishmaniasis, which is one of the most important emerging infectious diseases in the Americas. In the state of Amazonas in Brazil, anthropogenic activities encourage the presence of these insects around rural homes. The present study aimed to describe the composition and distribution of sand fly species diversity among the ecotopes (intradomicile, peridomicile and forest) in an area of American cutaneous leishmaniasis transmission and detect natural infection with Leishmania DNA to evaluate which vectors are inside houses and whether the presence of possible vectors represents a hazard of transmission.

Results

Phlebotomine sand flies were collected using light traps. A total of 2469 specimens representing 54 species, predominantly females (71.2%), were collected from four sites. Polymerase chain reaction analysis was performed on 670 samples to detect Leishmania DNA. Most of the samples (79.5%) were collected in the forest, with areas closer to rural dwellings yielding a greater abundance of suspected or proven vectors and a larger number of species containing Leishmania DNA. Nyssomyia umbratilis and Bichromomyia flaviscutellata were found near rural homes, and Ny. umbratilis was also found inside homes. Leishmania DNA was detected in different species of sand flies in all ecotopes, including species with no previous record of natural infection.

Conclusions

There is no evidence that vectors of American cutaneous leishmaniasis are becoming established inside homes, but there are sand flies, including Ny. umbratilis and other possible vectors, in environments characterized by a human presence. These species continue to be predominant in the forest but are prevalent in areas closer to ecotopes with a greater human presence. The existence of proven or suspected vectors in this ecotope is due to the structural organization of rural settlements and may represent a hazard of transmission. Although the detection of Leishmania DNA in species that were not previously considered vectors does not mean that they are transmitting the parasite, it does show that the parasite is circulating in ecotopes where these species are found.

Long-Term Peritoneal Dialysis Experience in Portugal

Peritoneal dialysis (PD) penetration varies widely. Since the beginning of this therapy, indications have changed and outcomes have improved. In Portugal, PD still remains clearly underutilized.

The results of a 20 year PD programme were evaluated: 312 cumulative patients, 48±16 years, 27% >60 years old, 27% diabetic, 59% with prior hemodialysis (HD). The main reason for admission was vascular access failure (48.7%). Admission due to patient preference has increased significantly between first and second decades of the programme (33% vs 47% (P<0.001)); 98 patients (31.4%) were treated with automated PD but this prescription increased to 43% of the active patients.

A total of 376 Tenckhoff catheters were surgically implanted, recently by the Popovich-Moncrief technique (77 catheters): the cumulative survival was 82%, 64% and 50% at 1, 3 and 5 years, respectively. A better catheter survival was found in the last decade (85.7%, 69.6%, 54.8% versus 77.3%, 55.5%, 40.2%, at 1, 3 and 5 years, respectively (P=0.007).

The patient and technique cumulative survivals were 91, 74, 55% and 85, 67, 41%, at 1, 3, and 5 years, respectively.

The main drop-out was to hemodialysis (35.8%), followed by death (23.7%), and transplantation (21.5%). Peritonitis and access-related infections caused 35% of the transfer to HD. Cardiovascular events caused 58% of deaths. The median PD retention was 35.5 months. The rate of peritonitis has decreased to one episode /30 patient months. Hospital admission has also decreased to 4.8 days/patient year.

This is a first report on long-term PD experience in Portugal. It has been an effective modality of renal replacement therapy, reflected by the growing patient preference in our PD programme. Experience, knowledge and new technical solutions have improved the outcomes.

Intensity of swimming exercise influences aortic reactivity in rats

Exercise is known to cause a vasodilatory response; however, the correlation between the vasorelaxant response and different training intensities has not been investigated. Therefore, this study evaluated the vascular reactivity and lipid peroxidation after different intensities of swimming exercise in rats. Male Wistar rats (aged 8 weeks; 250-300 g) underwent forced swimming for 1 h whilst tied to loads of 3, 4, 5, 6, and 8% of their body weight, respectively (groups G3, G4, G5, G6 and G8, respectively; n=5 each). Immediately after the test, the aorta was removed and suspended in an organ bath. Cumulative relaxation in response to acetylcholine (10⁻¹²-10⁻⁴ M) and contraction in response to phenylephrine (10⁻¹²-10⁻⁵ M) were measured. Oxidative stress was estimated by determining malondialdehyde concentration. The percentages of aorta relaxation were significantly higher in G3 (7.9±0.20), G4 (7.8±0.29), and G5 (7.9±0.21), compared to the control group (7.2±0.04), while relaxation in the G6 (7.4±0.25) and G8 (7.0±0.06) groups was similar to the control group. In contrast, the percentage of contraction was significantly higher in G6 (8.8 ±0.1) and G8 (9.7±0.29) compared to the control (7.1±0.1), G3 (7.3±0.2), G4 (7.2±0.1) and G5 (7.2±0.2%) groups. Lipid peroxidation levels in the aorta were similar to control levels in G3, G4 and G5, but higher in G6 and G8, and significantly higher in G8 (one-way ANOVA). These results indicate a reduction in vasorelaxing activity and an increase in contractile activity in rat aortas after high-intensity exercise, followed by an increase in lipid peroxidation.

Performance of glycated haemoglobin (HbA1c) as a screening test for diabetes and impaired glucose tolerance (IGT) in a high risk population--the Brazilian Xavante Indians

AIMS

To examine the properties of HbA1c to detect diabetes and IGT in adult Brazilian Xavante Indians, a high risk population for diabetes.

METHODS

The survey was carried out between October 2010 and January 2012 and based on a 75 g oral glucose tolerance test (OGTT). Basal and 2h capillary glycaemia were measured by HemoCue Glucose 201+; HbA1c using an automated high-performance liquid chromatography analyzer (Tosoh G7).

RESULTS

630 individuals aged ≥ 20 years were examined and 80 had a previous diagnosis of diabetes. Sensitivity, specificity and accuracy for HbA1c ≥ 6.5% (≥ 48 mmol/mol) were 71.3%, 90.5% and 87.2%. The areas under the ROC curve (AUC) was 0.88 (95%CI: 0.83-0.93). To identify IGT, HbA1c values between 5.7% and 6.4% (39-47 mmol/mol) presented sensitivity, specificity and accuracy of 87.2%, 24.7% and 51.4%, with an AUC of 0.62 (95%CI: 0.57-0.67).

CONCLUSIONS

The ADA/WHO proposed cut-off of 6.5% (48 mmol/mol) for HbA1c was adequate to detect diabetes among the Xavante. However, the performance of the ADA proposed cut-off points for pre-diabetes, when used to detect IGT was inadequate and should not be recommended.

HLA-A, HLA-B and HLA-DRB1 haplotype frequencies in Piauí's volunteer bone marrow donors enrolled at the Brazilian registry

This study aimed to report the antigen and haplotype frequencies (HFs) of volunteer bone marrow donors (VBMDs) from the state of Piauí who were enrolled in the National Volunteer Bone Marrow Donor Registry (REDOME). The research subjects were 21,943 volunteer bone marrow donors, predominantly young adult women (53.3%). The most frequent allelic group was HLA-A2, followed by -DRB1*13, -DRB1*04, -DRB1*07, -B*15, -B∗35, -B*44, -A*24 and -A*03. Of the 2,704 haplotypes observed, the three most frequent haplotypes were A*29 B*44 DRB1*07 (1.45%), A*01 B*08 DRB1*03 (1.4%) and A*03 B*07 DRB1*15 (0.92%). These three haplotypes were in linkage disequilibrium. PCA showed that 98% of the VBMDs have HLA allele frequencies that are very similar to those from Teresina, the capital city of Piauí. According to the PCA results, these municipalities are distributed with a close proximity to Teresina, which in turn has a close genetic proximity to the Hispanic ethnicity, intermediate proximity to Caucasians and Africans and a distant kinship to Amerindians. The hierarchical proximity of the population of Piauí to the Portuguese and Hispanic populations to shows the strong influence of the latter on the former.

Properties of catechol 1,2-dioxygenase in the cell free extract and immobilized extract of Mycobacterium fortuitum

Polycyclic aromatic hydrocarbons (PAH) are carcinogenic compounds which contaminate water and soil, and the enzymes can be used for bioremediation of these environments. This study aimed to evaluate some environmental conditions that affect the production and activity of the catechol 1,2-dioxygenase (C12O) by Mycobacterium fortuitum in the cell free and immobilized extract in sodium alginate. The bacterium was grown in mineral medium and LB broth containing 250 mg L⁻¹ of anthracene (PAH). The optimum conditions of pH (4.0–9.0), temperature (5–70 °C), reaction time (10–90 min) and the effect of ions in the enzyme activity were determined. The Mycobacterium cultivated in LB shown higher growth and the C12O activity was two-fold higher to that in the mineral medium. To both extracts the highest enzyme activity was at pH 8.0, however, the immobilized extract promoted the increase in the C12O activity in a pH range between 4.0 and 8.5. The immobilized extract increased the enzymatic activity time and showed the highest C12O activity at 45 °C, 20 °C higher than the greatest temperature in the cell free extract. The enzyme activity in both extracts was stimulated by Fe³⁺, Hg²⁺ and Mn²⁺ and inhibited by NH⁴⁺ and Cu²⁺, but the immobilization protected the enzyme against the deleterious effects of K⁺ and Mg²⁺ in tested concentrations. The catechol 1,2-dioxygenase of Mycobacterium fortuitum in the immobilized extract has greater stability to the variations of pH, temperature and reaction time, and show higher activity in presence of ions, comparing to the cell free extract.

Best impression materials in oral rehabilitation-study protolocol

Short Communication selected from the Oral Presentations of the 56th Congress of the Groupèment International pour la Recherche Scientifique en Stomatologie et Odontologie, Peñafiel (Portugal) May 2012.

Study of mural paintings using in situ XRF, confocal synchrotron-μ-XRF, μ-XRD, optical microscopy, and SEM-EDS--the case of the frescoes from Misericordia Church of Odemira

In this work, we present the results of an analytical method developed for detailed pigment identification, stratigraphy, and degradation of the paint layers of mural paintings applied in the study of the 17th century frescoes from the Misericordia Church of Odemira (Southwest Portugal). In situ X-ray fluorescence spectrometry analyses were performed on three panels of the mural paintings and complemented by colorimetric measurements. The different color areas were also sampled as microfragments (approx. 1 mm2) that were studied as taken or mounted in epoxy resin to expose the different paint layers. The microfragments of paint layers and their cross sections were characterized by optical microscopy and scanning electron microscopy coupled with energy dispersive X-ray spectrometry. Furthermore, elemental analysis was obtained with spatially resolved confocal synchrotron radiation μ-X-ray fluorescence spectrometry performed at ANKA synchrotron FLUO beamline. Occasionally, phase analysis by μ-X-ray diffraction was also performed. Results from the different techniques allowed pigment identification and, in some cases, the evaluation of color changes due to degradation processes and, considering the Southern Portugal geology, the identification of their possible provenance. The pigments used were essentially yellow, brown and red ochres, smalt blue, copper green, and black earths, probably from local sources.

Evaluation of miltefosine for the treatment of dogs naturally infected with L. infantum (=L. chagasi) in Brazil

Dogs naturally infected with Leishmania Infantum (=L. chagasi) were treated with miltefosine using different therapeutic regimens. The animals were evaluated for clinical evolution, biochemical parameters, parasite load (by real-time PCR), cytokine levels and humoral response. After treatment and during the following 24 months, there was progressive clinical improvement and complete recovery in 50% (7/14) of the treated animals. There was a decrease in the smear positivity of the bone marrow after treatment, and there was also a gradual and constant decrease in positive cultures at the end of the follow-up period. However, the PCR detection of parasite DNA remained positive. In general, all animals presented a significant increase in parasite load 6 months after treatment. The IFN-γ levels in all the groups tended to increase during follow-up period, regardless of the miltefosine dose administered. The IL-4 and IL-10 levels of the animals tended to decrease during follow-up, except after 300 days when only IL-10 increased. The serum antibodies identified antigens that ranged from 116 kDa to less than 29 kDa in the Western blot assay. Furthermore, 300 days after treatment, qualitative and quantitative differences in the antigen profiles were observed. Antigens of 97 and 46 kDa were the most intensely recognized. Higher levels of antigen-specific Leishmania IgG were detected before and 300 days after treatment in all groups. Taking together, the improvement in the clinical symptoms was not followed by parasitological clearance, suggesting that treatment with miltefosine is not recommended, especially in endemic areas like Brazil, where children are the major victims and dogs are involved in the maintenance of the parasite cycle.

Tailoring magnetic nanoparticle for transformers application

In this study photoacoustic spectroscopy was used to investigate the effect of dilution of an oil-based magnetic fluid sample on the magnetic nanoparticle surface-coating. Changes of the photoacoustic signal intensity on the band-L region (640 to 830 nm) upon dilution of the stock magnetic fluid sample were discussed in terms of molecular surface desorption. The model proposed here assumes that the driving force taking the molecules out from the nanoparticle surface into the bulk solvent is the gradient of osmotic pressure. This gradient of osmotic pressure is established between the nanoparticle surface and the bulk suspension. It is further assumed that the photoacoustic signal intensity (area under the photoacoustic spectra) scales linearly with the number of coating molecules (surface grafting) at the nanoparticle surface. This model picture provides a non-linear analytical description for the reduction of the surface grafting coefficient upon dilution, which was successfully-used to curve-fit the photoacoustic experimental data.

Association between a new 3q;5q chromosomal translocation and dystrophy of human retinal pigment epithelium

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal degeneration. This group of disorders essentially leads to blindness due to mutations in different genes. The genetic basis affected by sporadic and inherited autosomal dominant, autosomal recessive or X-linked mutations is complex. In humans, RP is in most cases associated with missense mutations in the rhodopsin gene (RHO). RHO plays an important role in phototransduction pathways. So far, few studies have described associations between chromosomal alterations and RP. In this study, we present a case report of a premature, 32-week-old male baby who suffered from retinopathy, facial dysmorphisms and other disorders. His chromosomes were analyzed by conventional and high-resolution chromosomal techniques. This analysis revealed structural aberrations on chromosomes 3 and 5 with an apparently balanced chromosomal translocation with karyotype 46,XY,t(3;5)(q25;q11.2). Remarkably, the 3q breakpoint on the long arm of chromosome 3 is located close to the physical RHO chromosomal gene location. In this study, we describe presumably for the first time a possible association between a 3q;5q chromosomal alteration and RP. We conclude that the new detected chromosomal translocation may lead either to loss or inactivation of the intragenic RHO gene or its respective gene regulatory region. As a consequence, the chromosomal aberration may be responsible for retinitis pigmentosa.

Effects of velnacrine maleate in the leukocyte-endothelial cell interactions in rat cremaster microcirculatory network

The expression of acetylcholinesterase in proinflammatory cells has supported the hypothesis that this protein plays a role in intercellular adhesion. Previous results of our group show that velnacrine, an acetylcholinesterase inhibitor, increases the number of adherent leukocytes in post-capillary venules of Wistar rats' mesentery muscle. This works intends to evaluate the local application of velnacrine and acetylcholine in the inflammatory response at the microcirculatory network by studying the leukocytes/endothelium interactions in post-capillary venules of Wistar rats' cremaster muscle. The number and the speed of the rolling leukocytes, the number of adherent leukocytes and hemodynamic parameters were determined and also the plasma levels of IL-1beta. The results have shown that in the presence of velnacrine there is a significant increase of the rolling leukocytes (1.28+/-0.39 vs 1.93+/-0.20), as well as an increase of the adherent ones (0.86+/-0.72 vs 1.02+/-0.83). When acetylcholine is adding with velnacrine the number of rolling and adherent leukocytes decreases without changing the IL-1beta plasma circulation induced by velnacrine. Our results suggest an anti-inflammatory role induced by ACh without full efficiency because the rolling leukocytes velocity was reduced without changes in the plasma level of IL-1beta.

Conservation of glycolytic oscillations in Saccharomyces cerevisiae and human pancreatic beta-cells: a study of metabolic robustness

The present study compares two computer models of the first part of glucose catabolism in different organisms in search of evolutionarily conserved characteristics of the glycolysis cycle and proposes the main parameters that define the stable steady-state or oscillatory behavior of the glycolytic system. It is suggested that in both human pancreatic beta-cells and Saccharomyces cerevisiae there are oscillations that, despite differences in wave form and period of oscillation, share the same robustness strategy: the oscillation is not controlled by only one but by at least two parameters that will have more or less control over the pathway flux depending on the initial state of the system as well as on extra-cellular conditions. This observation leads to two important interpretations: the first is that in both S. cerevisiae and human beta-cells, despite differences in enzyme kinetics and mechanism of feedback control, evolution seems to have kept an oscillatory behavior coupled to the glucose concentration outside the cytoplasm, and the second is that the development of drugs to regulate metabolic dysfunctions in more complex systems may require further study, not only determining which enzyme is controlling the flux of the system but also under which conditions and how its control is maintained by the enzyme or transferred to other enzymes in the pathway as the drug starts acting.

Phytosterols in milk as a depressor of plasma cholesterol levels: experimental evidence with hypercholesterolemic Portuguese subjects

Plant sterols have been reported to decrease plasma concentrations of cholesterol without any side effects. To evaluate the effects on plasma cholesterol concentrations and the hemorheological parameters, we performed a study with hypercholesterolemic patients (n = 19) treated with phytosterol-enriched milk (2 g/day). Hypercholesterolemic patients (n = 15) of matched age drinking equal type of milk but without phytosterols were used as control group. Concentrations of total cholesterol, HDL-C, LDL-C and hemorheological parameters were measured in the beginning, after 15 and 30 days of milk intake. After 15 days of beverage intake, hypercholesterolemic subjects treated with phytosterol-enriched milk showed a significant decrease in plasma concentrations of total cholesterol and LDL-C by 9.62% (p < 0.05) and 12.20% (p < 0.05), respectively. After 30 days, a little increase in the total cholesterol and LDL-C concentrations were observed. In the hypercholesterolemic control group there were nonsignificant changes between plasma concentrations of total cholesterol, HDL-C and LDL-C during the study. The evaluation of plasma viscosity and erythrocyte aggregation shows no changes statistically significant during the study for both groups studied. The results obtained during the study show a positive effect with the phytosterol-enriched milk as plasma cholesterol-lowering as combined treatment for hypercholesterolemia.

Effects of low-fat milk enriched with phytosterols on plasma cholesterol concentrations and hemorheological parameters of Wistar rats

Clinical and experimental studies have shown that the use of phytosterol esters as a food ingredient reduces the plasma concentrations of cholesterol and LDL cholesterol, not affecting the HDL cholesterol levels. Based on the use of phytosterols as a food ingredient, we have conducted a 30-day feeding study with Wistar rats, drinking low-fat milk containing phytosterols, in order to evaluate the plasma cholesterol concentrations and the hemorheological parameters. Throughout the study, clinical observations, body weights and food and milk consumption were measured and at the end of the feeding period, blood samples were collected for biochemical and hemorheological determinations. There were no clinical changes, alterations in growth, food or milk consumption. In the plasma cholesterol and HDL concentrations there were no significant differences, but LDL levels decreased about 70%. In the hemorheological parameters, significant changes were observed in plasma viscosity and in membrane fluidity in all experimental groups. The blood viscosity and the erythrocyte deformability show significant improvements with the ingestion of the phytosterols enriched milk. With these results we conclude that phytosterols maintain their cholesterol lowering properties when incorporated in milk and can be considered a hypolipemic food component.

Methotrexate as a preferential cyclooxygenase 2 inhibitor in whole blood of patients with rheumatoid arthritis

OBJECTIVE

To investigate the regulation of whole-blood cyclooxygenase-1 and -2 (COX-2 and COX-1) activities by methotrexate (MTX) in rheumatoid arthritis (RA) patients.

METHODS

Whole blood was withdrawn from nine healthy volunteers, 12 RA patients treated with MTX (RA/MTX) and six RA patients treated with chloroquine (RA/CQ). COX-1 activity was quantified as platelet thromboxane B(2) production in unstimulated blood and COX-2 activity was measured as prostaglandin E(2) (PGE(2)) production in whole blood stimulated with LPS. Thromboxane B(2) and PGE(2) were measured by radioimmunoassay. We studied the drug effect in vitro by direct incubation of MTX with blood obtained from normal donors. Ex vivo assays were performed with blood collected from RA/MTX and RA/CQ patients. The influence of serum factors on enzyme activities was analysed in blood collected from normal donors and incubated with RA/MTX, autologous or heterologous serum.

RESULTS

In vitro assays showed no direct action of MTX on the activity of either enzyme. Assays performed with blood from RA/MTX patients showed preferential inhibition of COX-2 activity (PGE(2) = 10.11 +/- 2.42 ng/ml) when compared with blood of normal donors (PGE(2) = 37.7 +/- 4.36 ng/ml; P = 0.001). Inhibition of COX-2 activity was also observed when blood of normal donors was co-incubated with RA/MTX serum.

CONCLUSION

Our results clearly show that the anti-inflammatory action of low-dose MTX is partly mediated by a serum factor induced by MTX or a MTX metabolite that preferentially inhibits the activity of COX-2.

Treatment of morbid obesity with adjustable gastric band: preliminary report

BACKGROUND

The goal of surgery for morbid obesity is to achieve a good and durable loss of weight and improve health. Previous studies have demonstrated a significant weight loss for the Swedish adjustable gastric band (SAGB).

PATIENTS AND METHODS

Between November 1996 and April 1998, 18 morbidly obese patients underwent SAGB laparoscopically. Their mean age at surgery was 35 years. The mean preoperative weight was 128 kg (range 89-163), and the mean body mass index was 50.4+/-9. Comorbidity was present in 13 patients.

RESULTS

One gastric perforation occurred, and in one patient it was not possible to create the pneumoperitoneum. Regarding late morbidity, one intragastric migration and one slippage of the band occurred. There was no mortality.

CONCLUSION

The low morbidity, the good results with weight loss, and the improvement in comorbidity lead the authors to believe that Swedish adjustable gastric banding for the treatment of morbidly obese patients is a successful means of losing weight and improving general health.